[Enhanced expression of caveolin-1 in articular chondrocytes in osteoarthritis].
OBJECTIVE
To study the expression level of caveolin-1 in articular chondrocytes in patients with osteoarthritis (OA), and whether catabolic factor IL-1beta stimulate caveolin-1 expression in articular chondrocytes.


METHODS
In human OA cartilage, caveolin-1 mRNA was investigated by quantitative real-time RT-PCR while caveolin-1 protein was detected by immunohistologic analysis in 8 cases. OA model was prepared by unilateral anterior cruciate ligament and medial collateral ligament transection in 20 rats. In cultured OA chondrocytes, caveolin-1 mRNA expression was studied by RT-PCR and quantitative real-time RT-PCR, and caveolin-1 protein was analyzed by Western blotting.


RESULTS
In 6 of 8 OA cases, human OA articular cartilage, higher expression levels of both caveolin-1 mRNA and caveolin-1 protein were found in advanced degenerated cartilage than less degenerated cartilage of the same joints. In rat OA model, upregulated caveolin-1 expression was found, which was associated with the degree of cartilage destruction. IL-1beta (10 ng/ml) upregulated caveolin-1 mRNA/protein expression in cultured OA chondrocytes for at least 48 hours.


CONCLUSIONS
Enhanced expression level of caveolin-1 is associated with cartilage degeneration in OA. IL-1beta stimulates caveolin-1 expression in articular chondrocytes, which may be responsible for OA development.
Tang
Yue-qiong
YQ
Department of Rheumatology & Immunology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.
Shan
Zheng-zheng
ZZ
Dai
Sheng-ming
SM
D000368:Aged; D000818:Animals; D015153:Blotting, Western; D051242:Caveolin 1 / Q000096:biosynthesis* / Q000235:genetics; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D053583:Interleukin-1beta / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
D051242:Caveolin 1; D053583:Interleukin-1beta; D012333:RNA, Messenger